var http = require('http')
var util = require('util')
var fs = require('fs')

var express = require('express')
var validator = require('express-validator')
var formidable = require('formidable')
var Promise = require('bluebird')
var ApkReader = require('adbkit-apkreader')
var request = require('request')
var progress = require('request-progress')
var temp = require('temp')
var zmq = require('zmq')

var logger = require('../../util/logger')
var requtil = require('../../util/requtil')
var Storage = require('../../util/storage')
var wireutil = require('../../wire/util')

module.exports = function(options) {
  var log = logger.createLogger('storage-temp')
    , app = express()
    , server = http.createServer(app)
    , storage = new Storage()

  // Output
  var push = zmq.socket('push')
  options.endpoints.push.forEach(function(endpoint) {
    log.info('Sending output to %s', endpoint)
    push.connect(endpoint)
  })

  app.set('strict routing', true)
  app.set('case sensitive routing', true)
  app.set('trust proxy', true)

  app.use(express.json())
  app.use(validator())

  storage.on('timeout', function(id) {
    log.info('Cleaning up inactive resource "%s"', id)
  })

  function processFile(file) {
    var resolver = Promise.defer()

    log.info('Processing file "%s"', file.path)

    resolver.progress({
      percent: 0
    })

    process.nextTick(function() {
      try {
        var reader = ApkReader.readFile(file.path)
        var manifest = reader.readManifestSync()
        resolver.resolve(manifest)
      }
      catch (err) {
        err.reportCode = 'fail_invalid_app_file'
        resolver.reject(err)
      }
    })

    return resolver.promise
  }

  function storeFile(file) {
    var id = storage.store(file)
    return Promise.resolve({
      id: id
    , url: util.format(
        'http://%s:%s/api/v1/resources/%s'
      , options.publicIp
      , options.port
      , id
      )
    })
  }

  function download(url) {
    var resolver = Promise.defer()
    var path = temp.path({
      dir: options.saveDir
    })

    log.info('Downloading "%s" to "%s"', url, path)

    function errorListener(err) {
      err.reportCode = 'fail_download'
      resolver.reject(err)
    }

    function progressListener(state) {
      resolver.progress(state)
    }

    function closeListener() {
      resolver.resolve({
        path: path
      })
    }

    resolver.progress({
      percent: 0
    })

    try {
      var req = progress(request(url), {
          throttle: 100 // Throttle events, not upload speed
        })
        .on('progress', progressListener)

      var save = req.pipe(fs.createWriteStream(path))
        .on('error', errorListener)
        .on('close', closeListener)
    }
    catch (err) {
      err.reportCode = 'fail_invalid_url'
      resolver.reject(err)
    }

    return resolver.promise.finally(function() {
      req.removeListener('progress', progressListener)
      save.removeListener('error', errorListener)
      save.removeListener('close', closeListener)
    })
  }

  app.post('/api/v1/resources', function(req, res) {
    var reply = wireutil.reply(options.id)

    function sendProgress(data, progress) {
      if (req.query.channel) {
        push.send([
          req.query.channel
        , reply.progress(data, progress)
        ])
      }
    }

    function sendDone(success, data, body) {
      if (req.query.channel) {
        push.send([
          req.query.channel
        , reply.okay(data, body)
        ])
      }
    }

    requtil.validate(req, function() {
        req.checkQuery('channel').notEmpty()
      })
      .then(function() {
        if (req.is('application/json')) {
          return requtil.validate(req, function() {
              req.checkBody('url').notEmpty()
            })
            .then(function() {
              return download(req.body.url)
                .progressed(function(progress) {
                  sendProgress('uploading', 0.7 * progress.percent)
                })
            })
        }
        else {
          var form = Promise.promisifyAll(new formidable.IncomingForm())
          function progressListener(received, expected) {
            if (expected) {
              sendProgress('uploading', 70 * (received / expected))
            }
          }
          sendProgress('uploading', 0)
          form.on('progress', progressListener)
          return form.parseAsync(req)
            .finally(function() {
              form.removeListener('progress', progressListener)
            })
            .spread(function(fields, files) {
              if (!files.file) {
                throw new requtil.ValidationError('validation error', [
                  {
                    "param": "file"
                  , "msg": "Required value"
                  }
                ])
              }
              return files.file
            })
        }
      })
      .then(function(file) {
        return processFile(file)
          .progressed(function(progress) {
            sendProgress('processing', 70 + 0.2 * progress.percent)
          })
          .then(function(manifest) {
            sendProgress('storing', 90)
            return storeFile(file)
              .then(function(data) {
                data.manifest = manifest
                return data
              })
          })
      })
      .then(function(data) {
        sendDone(true, 'success', data)
        data.success = true
        res.json(201, data)
      })
      .catch(requtil.ValidationError, function(err) {
        sendDone(false, err.reportCode || 'fail_validation')
        res.status(400)
          .json({
            success: false
          , error: 'ValidationError'
          , validationErrors: err.errors
          })
      })
      .catch(function(err) {
        log.error('Unexpected error', err.stack)
        sendDone(false, err.reportCode || 'fail')
        res.status(500)
          .json({
            success: false
          , error: 'ServerError'
          })
      })
  })

  app.get('/api/v1/resources/:id', function(req, res) {
    var file = storage.retrieve(req.params.id)
    if (file) {
      res.set('Content-Type', file.type)
      res.sendfile(file.path)
    }
    else {
      res.send(404)
    }
  })

  server.listen(options.port)
  log.info('Listening on port %d', options.port)
}